diff --git a/src/Avatar.ts b/src/Avatar.ts
index a6499c688e..8ea0b0c9fa 100644
--- a/src/Avatar.ts
+++ b/src/Avatar.ts
@@ -14,18 +14,23 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import {RoomMember} from "matrix-js-sdk/src/models/room-member";
-import {User} from "matrix-js-sdk/src/models/user";
-import {Room} from "matrix-js-sdk/src/models/room";
+import { RoomMember } from "matrix-js-sdk/src/models/room-member";
+import { User } from "matrix-js-sdk/src/models/user";
+import { Room } from "matrix-js-sdk/src/models/room";
 
 import DMRoomMap from './utils/DMRoomMap';
-import {mediaFromMxc} from "./customisations/Media";
+import { mediaFromMxc } from "./customisations/Media";
 import SettingsStore from "./settings/SettingsStore";
 
 export type ResizeMethod = "crop" | "scale";
 
 // Not to be used for BaseAvatar urls as that has similar default avatar fallback already
-export function avatarUrlForMember(member: RoomMember, width: number, height: number, resizeMethod: ResizeMethod) {
+export function avatarUrlForMember(
+    member: RoomMember,
+    width: number,
+    height: number,
+    resizeMethod: ResizeMethod,
+): string {
     let url: string;
     if (member?.getMxcAvatarUrl()) {
         url = mediaFromMxc(member.getMxcAvatarUrl()).getThumbnailOfSourceHttp(width, height, resizeMethod);
@@ -39,7 +44,12 @@ export function avatarUrlForMember(member: RoomMember, width: number, height: nu
     return url;
 }
 
-export function avatarUrlForUser(user: User, width: number, height: number, resizeMethod?: ResizeMethod) {
+export function avatarUrlForUser(
+    user: Pick<User, "avatarUrl">,
+    width: number,
+    height: number,
+    resizeMethod?: ResizeMethod,
+): string | null {
     if (!user.avatarUrl) return null;
     return mediaFromMxc(user.avatarUrl).getThumbnailOfSourceHttp(width, height, resizeMethod);
 }
diff --git a/src/Searching.js b/src/Searching.js
index 2b17aee054..596dd2f3d4 100644
--- a/src/Searching.js
+++ b/src/Searching.js
@@ -468,7 +468,7 @@ function restoreEncryptionInfo(searchResultSlice = []) {
                     ev.event.curve25519Key,
                     ev.event.ed25519Key,
                 );
-                ev._forwardingCurve25519KeyChain = ev.event.forwardingCurve25519KeyChain;
+                ev.forwardingCurve25519KeyChain = ev.event.forwardingCurve25519KeyChain;
 
                 delete ev.event.curve25519Key;
                 delete ev.event.ed25519Key;
diff --git a/src/autocomplete/UserProvider.tsx b/src/autocomplete/UserProvider.tsx
index 3cf43d0b84..687b477133 100644
--- a/src/autocomplete/UserProvider.tsx
+++ b/src/autocomplete/UserProvider.tsx
@@ -20,19 +20,19 @@ limitations under the License.
 import React from 'react';
 import { _t } from '../languageHandler';
 import AutocompleteProvider from './AutocompleteProvider';
-import {PillCompletion} from './Components';
+import { PillCompletion } from './Components';
 import * as sdk from '../index';
 import QueryMatcher from './QueryMatcher';
-import {sortBy} from 'lodash';
-import {MatrixClientPeg} from '../MatrixClientPeg';
+import { sortBy } from 'lodash';
+import { MatrixClientPeg } from '../MatrixClientPeg';
 
-import MatrixEvent from "matrix-js-sdk/src/models/event";
-import Room from "matrix-js-sdk/src/models/room";
-import RoomMember from "matrix-js-sdk/src/models/room-member";
-import RoomState from "matrix-js-sdk/src/models/room-state";
-import EventTimeline from "matrix-js-sdk/src/models/event-timeline";
-import {makeUserPermalink} from "../utils/permalinks/Permalinks";
-import {ICompletion, ISelectionRange} from "./Autocompleter";
+import { MatrixEvent } from "matrix-js-sdk/src/models/event";
+import { Room } from "matrix-js-sdk/src/models/room";
+import { RoomMember } from "matrix-js-sdk/src/models/room-member";
+import { RoomState } from "matrix-js-sdk/src/models/room-state";
+import { EventTimeline } from "matrix-js-sdk/src/models/event-timeline";
+import { makeUserPermalink } from "../utils/permalinks/Permalinks";
+import { ICompletion, ISelectionRange } from "./Autocompleter";
 
 const USER_REGEX = /\B@\S*/g;
 
diff --git a/src/components/structures/RoomView.tsx b/src/components/structures/RoomView.tsx
index c9645515bf..1e3adcb518 100644
--- a/src/components/structures/RoomView.tsx
+++ b/src/components/structures/RoomView.tsx
@@ -25,6 +25,7 @@ import React, { createRef } from 'react';
 import classNames from 'classnames';
 import { Room } from "matrix-js-sdk/src/models/room";
 import { MatrixEvent } from "matrix-js-sdk/src/models/event";
+import { SearchResult } from "matrix-js-sdk/src/models/search-result";
 import { EventSubscription } from "fbemitter";
 
 import shouldHideEvent from '../../shouldHideEvent';
@@ -142,7 +143,7 @@ export interface IState {
     searchResults?: XOR<{}, {
         count: number;
         highlights: string[];
-        results: MatrixEvent[];
+        results: SearchResult[];
         next_batch: string; // eslint-disable-line camelcase
     }>;
     searchHighlights?: string[];
diff --git a/src/components/views/dialogs/DevtoolsDialog.tsx b/src/components/views/dialogs/DevtoolsDialog.tsx
index fdbf6a36fc..2690eb67d7 100644
--- a/src/components/views/dialogs/DevtoolsDialog.tsx
+++ b/src/components/views/dialogs/DevtoolsDialog.tsx
@@ -525,11 +525,11 @@ class RoomStateExplorer extends React.PureComponent<IExplorerProps, IRoomStateEx
 }
 
 interface IAccountDataExplorerState {
+    [inputId: string]: boolean | string | any;
     isRoomAccountData: boolean;
     event?: MatrixEvent;
     editing: boolean;
     queryEventType: string;
-    [inputId: string]: boolean | string;
 }
 
 class AccountDataExplorer extends React.PureComponent<IExplorerProps, IAccountDataExplorerState> {
diff --git a/src/components/views/dialogs/InviteDialog.tsx b/src/components/views/dialogs/InviteDialog.tsx
index 778744b783..ffca9a88a7 100644
--- a/src/components/views/dialogs/InviteDialog.tsx
+++ b/src/components/views/dialogs/InviteDialog.tsx
@@ -153,8 +153,8 @@ class ThreepidMember extends Member {
 }
 
 interface IDMUserTileProps {
-    member: RoomMember;
-    onRemove(member: RoomMember): void;
+    member: Member;
+    onRemove(member: Member): void;
 }
 
 class DMUserTile extends React.PureComponent<IDMUserTileProps> {
@@ -168,7 +168,7 @@ class DMUserTile extends React.PureComponent<IDMUserTileProps> {
 
     render() {
         const avatarSize = 20;
-        const avatar = this.props.member.isEmail
+        const avatar = (this.props.member as ThreepidMember).isEmail
             ? <img
                 className='mx_InviteDialog_userTile_avatar mx_InviteDialog_userTile_threepidAvatar'
                 src={require("../../../../res/img/icon-email-pill-avatar.svg")}
@@ -210,9 +210,9 @@ class DMUserTile extends React.PureComponent<IDMUserTileProps> {
 }
 
 interface IDMRoomTileProps {
-    member: RoomMember;
+    member: Member;
     lastActiveTs: number;
-    onToggle(member: RoomMember): void;
+    onToggle(member: Member): void;
     highlightWord: string;
     isSelected: boolean;
 }
@@ -270,7 +270,7 @@ class DMRoomTile extends React.PureComponent<IDMRoomTileProps> {
         }
 
         const avatarSize = 36;
-        const avatar = this.props.member.isEmail
+        const avatar = (this.props.member as ThreepidMember).isEmail
             ? <img
                 src={require("../../../../res/img/icon-email-pill-avatar.svg")}
                 width={avatarSize} height={avatarSize} />
@@ -298,7 +298,7 @@ class DMRoomTile extends React.PureComponent<IDMRoomTileProps> {
             </span>
         );
 
-        const caption = this.props.member.isEmail
+        const caption = (this.props.member as ThreepidMember).isEmail
             ? _t("Invite by email")
             : this.highlightName(this.props.member.userId);
 
@@ -334,7 +334,7 @@ interface IInviteDialogProps {
 }
 
 interface IInviteDialogState {
-    targets: RoomMember[]; // array of Member objects (see interface above)
+    targets: Member[]; // array of Member objects (see interface above)
     filterText: string;
     recents: { user: Member, userId: string }[];
     numRecentsShown: number;
diff --git a/src/components/views/elements/MemberEventListSummary.tsx b/src/components/views/elements/MemberEventListSummary.tsx
index 0290ef6d83..f10884ce9d 100644
--- a/src/components/views/elements/MemberEventListSummary.tsx
+++ b/src/components/views/elements/MemberEventListSummary.tsx
@@ -24,7 +24,7 @@ import { _t } from '../../../languageHandler';
 import { formatCommaSeparatedList } from '../../../utils/FormattingUtils';
 import { isValid3pidInvite } from "../../../RoomInvite";
 import EventListSummary from "./EventListSummary";
-import {replaceableComponent} from "../../../utils/replaceableComponent";
+import { replaceableComponent } from "../../../utils/replaceableComponent";
 
 interface IProps {
     // An array of member events to summarise
@@ -303,7 +303,7 @@ export default class MemberEventListSummary extends React.Component<IProps> {
         return res;
     }
 
-    private static getTransitionSequence(events: MatrixEvent[]) {
+    private static getTransitionSequence(events: IUserEvents[]) {
         return events.map(MemberEventListSummary.getTransition);
     }
 
@@ -315,7 +315,7 @@ export default class MemberEventListSummary extends React.Component<IProps> {
      * @returns {string?} the transition type given to this event. This defaults to `null`
      * if a transition is not recognised.
      */
-    private static getTransition(e: MatrixEvent): TransitionType {
+    private static getTransition(e: IUserEvents): TransitionType {
         if (e.mxEvent.getType() === 'm.room.third_party_invite') {
             // Handle 3pid invites the same as invites so they get bundled together
             if (!isValid3pidInvite(e.mxEvent)) {
diff --git a/src/components/views/messages/MVoiceMessageBody.tsx b/src/components/views/messages/MVoiceMessageBody.tsx
index d65de7697a..a7e3b1cd86 100644
--- a/src/components/views/messages/MVoiceMessageBody.tsx
+++ b/src/components/views/messages/MVoiceMessageBody.tsx
@@ -24,6 +24,7 @@ import {_t} from "../../../languageHandler";
 import {mediaFromContent} from "../../../customisations/Media";
 import {decryptFile} from "../../../utils/DecryptFile";
 import RecordingPlayback from "../voice_messages/RecordingPlayback";
+import {IMediaEventContent} from "../../../customisations/models/IMediaEventContent";
 
 interface IProps {
     mxEvent: MatrixEvent;
@@ -45,7 +46,7 @@ export default class MVoiceMessageBody extends React.PureComponent<IProps, IStat
 
     public async componentDidMount() {
         let buffer: ArrayBuffer;
-        const content = this.props.mxEvent.getContent();
+        const content: IMediaEventContent = this.props.mxEvent.getContent();
         const media = mediaFromContent(content);
         if (media.isEncrypted) {
             try {
diff --git a/src/components/views/messages/SenderProfile.tsx b/src/components/views/messages/SenderProfile.tsx
index 805f842fbc..883b2bd8a7 100644
--- a/src/components/views/messages/SenderProfile.tsx
+++ b/src/components/views/messages/SenderProfile.tsx
@@ -17,10 +17,10 @@
 import React from 'react';
 import Flair from '../elements/Flair.js';
 import FlairStore from '../../../stores/FlairStore';
-import {getUserNameColorClass} from '../../../utils/FormattingUtils';
+import { getUserNameColorClass } from '../../../utils/FormattingUtils';
 import MatrixClientContext from "../../../contexts/MatrixClientContext";
-import {replaceableComponent} from "../../../utils/replaceableComponent";
-import MatrixEvent from "matrix-js-sdk/src/models/event";
+import { replaceableComponent } from "../../../utils/replaceableComponent";
+import { MatrixEvent } from "matrix-js-sdk/src/models/event";
 
 interface IProps {
     mxEvent: MatrixEvent;
diff --git a/src/components/views/right_panel/EncryptionInfo.tsx b/src/components/views/right_panel/EncryptionInfo.tsx
index aa51965ac6..db59a88967 100644
--- a/src/components/views/right_panel/EncryptionInfo.tsx
+++ b/src/components/views/right_panel/EncryptionInfo.tsx
@@ -17,8 +17,9 @@ limitations under the License.
 import React from "react";
 
 import * as sdk from "../../../index";
-import {_t} from "../../../languageHandler";
-import {RoomMember} from "matrix-js-sdk/src/models/room-member";
+import { _t } from "../../../languageHandler";
+import { RoomMember } from "matrix-js-sdk/src/models/room-member";
+import { User } from "matrix-js-sdk/src/models/user";
 
 export const PendingActionSpinner = ({text}) => {
     const Spinner = sdk.getComponent('elements.Spinner');
@@ -31,7 +32,7 @@ export const PendingActionSpinner = ({text}) => {
 interface IProps {
     waitingForOtherParty: boolean;
     waitingForNetwork: boolean;
-    member: RoomMember;
+    member: RoomMember | User;
     onStartVerification: () => Promise<void>;
     isRoomEncrypted: boolean;
     inDialog: boolean;
@@ -55,7 +56,7 @@ const EncryptionInfo: React.FC<IProps> = ({
                 text = _t("Accept on your other login…");
             } else {
                 text = _t("Waiting for %(displayName)s to accept…", {
-                    displayName: member.displayName || member.name || member.userId,
+                    displayName: (member as User).displayName || (member as RoomMember).name || member.userId,
                 });
             }
         } else {
diff --git a/src/components/views/right_panel/UserInfo.tsx b/src/components/views/right_panel/UserInfo.tsx
index 67c0595906..0b37fb9dd6 100644
--- a/src/components/views/right_panel/UserInfo.tsx
+++ b/src/components/views/right_panel/UserInfo.tsx
@@ -147,7 +147,7 @@ async function openDMForUser(matrixClient: MatrixClient, userId: string) {
 
 type SetUpdating = (updating: boolean) => void;
 
-function useHasCrossSigningKeys(cli: MatrixClient, member: RoomMember, canVerify: boolean, setUpdating: SetUpdating) {
+function useHasCrossSigningKeys(cli: MatrixClient, member: User, canVerify: boolean, setUpdating: SetUpdating) {
     return useAsyncMemo(async () => {
         if (!canVerify) {
             return undefined;
@@ -972,7 +972,7 @@ interface IRoomPermissions {
     canInvite: boolean;
 }
 
-function useRoomPermissions(cli: MatrixClient, room: Room, user: User): IRoomPermissions {
+function useRoomPermissions(cli: MatrixClient, room: Room, user: RoomMember): IRoomPermissions {
     const [roomPermissions, setRoomPermissions] = useState<IRoomPermissions>({
         // modifyLevelMax is the max PL we can set this user to, typically min(their PL, our PL) && canSetPL
         modifyLevelMax: -1,
@@ -1029,7 +1029,7 @@ function useRoomPermissions(cli: MatrixClient, room: Room, user: User): IRoomPer
 }
 
 const PowerLevelSection: React.FC<{
-    user: User;
+    user: RoomMember;
     room: Room;
     roomPermissions: IRoomPermissions;
     powerLevels: IPowerLevelsContent;
@@ -1038,7 +1038,7 @@ const PowerLevelSection: React.FC<{
         return (<PowerLevelEditor user={user} room={room} roomPermissions={roomPermissions} />);
     } else {
         const powerLevelUsersDefault = powerLevels.users_default || 0;
-        const powerLevel = parseInt(user.powerLevel, 10);
+        const powerLevel = user.powerLevel;
         const role = textualPowerLevel(powerLevel, powerLevelUsersDefault);
         return (
             <div className="mx_UserInfo_profileField">
@@ -1049,13 +1049,13 @@ const PowerLevelSection: React.FC<{
 };
 
 const PowerLevelEditor: React.FC<{
-    user: User;
+    user: RoomMember;
     room: Room;
     roomPermissions: IRoomPermissions;
 }> = ({user, room, roomPermissions}) => {
     const cli = useContext(MatrixClientContext);
 
-    const [selectedPowerLevel, setSelectedPowerLevel] = useState(parseInt(user.powerLevel, 10));
+    const [selectedPowerLevel, setSelectedPowerLevel] = useState(user.powerLevel);
     const onPowerChange = useCallback(async (powerLevelStr: string) => {
         const powerLevel = parseInt(powerLevelStr, 10);
         setSelectedPowerLevel(powerLevel);
@@ -1232,7 +1232,7 @@ const BasicUserInfo: React.FC<{
         setPendingUpdateCount(pendingUpdateCount - 1);
     }, [pendingUpdateCount]);
 
-    const roomPermissions = useRoomPermissions(cli, room, member);
+    const roomPermissions = useRoomPermissions(cli, room, member as RoomMember);
 
     const onSynapseDeactivate = useCallback(async () => {
         const {finished} = Modal.createTrackedDialog('Synapse User Deactivation', '', QuestionDialog, {
@@ -1276,12 +1276,26 @@ const BasicUserInfo: React.FC<{
         );
     }
 
+    let memberDetails;
     let adminToolsContainer;
-    if (room && member.roomId) {
+    if (room && (member as RoomMember).roomId) {
+        // hide the Roles section for DMs as it doesn't make sense there
+        if (!DMRoomMap.shared().getUserIdForRoomId((member as RoomMember).roomId)) {
+            memberDetails = <div className="mx_UserInfo_container">
+                <h3>{ _t("Role") }</h3>
+                <PowerLevelSection
+                    powerLevels={powerLevels}
+                    user={member as RoomMember}
+                    room={room}
+                    roomPermissions={roomPermissions}
+                />
+            </div>;
+        }
+
         adminToolsContainer = (
             <RoomAdminToolsContainer
                 powerLevels={powerLevels}
-                member={member}
+                member={member as RoomMember}
                 room={room}
                 startUpdating={startUpdating}
                 stopUpdating={stopUpdating}>
@@ -1310,20 +1324,6 @@ const BasicUserInfo: React.FC<{
         spinner = <Spinner />;
     }
 
-    let memberDetails;
-    // hide the Roles section for DMs as it doesn't make sense there
-    if (room && member.roomId && !DMRoomMap.shared().getUserIdForRoomId(member.roomId)) {
-        memberDetails = <div className="mx_UserInfo_container">
-            <h3>{ _t("Role") }</h3>
-            <PowerLevelSection
-                powerLevels={powerLevels}
-                user={member}
-                room={room}
-                roomPermissions={roomPermissions}
-            />
-        </div>;
-    }
-
     // only display the devices list if our client supports E2E
     const cryptoEnabled = cli.isCryptoEnabled();
 
@@ -1350,8 +1350,7 @@ const BasicUserInfo: React.FC<{
     const setUpdating = (updating) => {
         setPendingUpdateCount(count => count + (updating ? 1 : -1));
     };
-    const hasCrossSigningKeys =
-        useHasCrossSigningKeys(cli, member, canVerify, setUpdating );
+    const hasCrossSigningKeys = useHasCrossSigningKeys(cli, member as User, canVerify, setUpdating);
 
     const showDeviceListSpinner = devices === undefined;
     if (canVerify) {
@@ -1360,9 +1359,9 @@ const BasicUserInfo: React.FC<{
             verifyButton = (
                 <AccessibleButton className="mx_UserInfo_field mx_UserInfo_verifyButton" onClick={() => {
                     if (hasCrossSigningKeys) {
-                        verifyUser(member);
+                        verifyUser(member as User);
                     } else {
-                        legacyVerifyUser(member);
+                        legacyVerifyUser(member as User);
                     }
                 }}>
                     {_t("Verify")}
@@ -1410,7 +1409,7 @@ const BasicUserInfo: React.FC<{
         <UserOptionsSection
             canInvite={roomPermissions.canInvite}
             isIgnored={isIgnored}
-            member={member}
+            member={member as RoomMember}
             isSpace={SettingsStore.getValue("feature_spaces") && room?.isSpaceRoom()}
         />
 
@@ -1429,13 +1428,15 @@ const UserInfoHeader: React.FC<{
     const cli = useContext(MatrixClientContext);
 
     const onMemberAvatarClick = useCallback(() => {
-        const avatarUrl = member.getMxcAvatarUrl ? member.getMxcAvatarUrl() : member.avatarUrl;
+        const avatarUrl = (member as RoomMember).getMxcAvatarUrl
+            ? (member as RoomMember).getMxcAvatarUrl()
+            : (member as User).avatarUrl;
         if (!avatarUrl) return;
 
         const httpUrl = mediaFromMxc(avatarUrl).srcHttp;
         const params = {
             src: httpUrl,
-            name: member.name,
+            name: (member as RoomMember).name || (member as User).displayName,
         };
 
         Modal.createDialog(ImageView, params, "mx_Dialog_lightbox", null, true);
@@ -1447,13 +1448,13 @@ const UserInfoHeader: React.FC<{
                 <div>
                     <MemberAvatar
                         key={member.userId} // to instantly blank the avatar when UserInfo changes members
-                        member={member}
+                        member={member as RoomMember}
                         width={2 * 0.3 * UIStore.instance.windowHeight} // 2x@30vh
                         height={2 * 0.3 * UIStore.instance.windowHeight} // 2x@30vh
                         resizeMethod="scale"
                         fallbackUserId={member.userId}
                         onClick={onMemberAvatarClick}
-                        urls={member.avatarUrl ? [member.avatarUrl] : undefined} />
+                        urls={(member as User).avatarUrl ? [(member as User).avatarUrl] : undefined} />
                 </div>
             </div>
         </div>
@@ -1470,7 +1471,11 @@ const UserInfoHeader: React.FC<{
         presenceCurrentlyActive = member.user.currentlyActive;
 
         if (SettingsStore.getValue("feature_custom_status")) {
-            statusMessage = member.user._unstable_statusMessage;
+            if ((member as RoomMember).user) {
+                statusMessage = member.user.unstable_statusMessage;
+            } else {
+                statusMessage = (member as unknown as User).unstable_statusMessage;
+            }
         }
     }
 
@@ -1501,7 +1506,7 @@ const UserInfoHeader: React.FC<{
         e2eIcon = <E2EIcon size={18} status={e2eStatus} isUser={true} />;
     }
 
-    const displayName = member.rawDisplayName || member.displayname;
+    const displayName = (member as RoomMember).rawDisplayName || (member as GroupMember).displayname;
     return <React.Fragment>
         { avatarElement }
 
diff --git a/src/components/views/right_panel/VerificationPanel.tsx b/src/components/views/right_panel/VerificationPanel.tsx
index ac01c953b9..edfe0e3483 100644
--- a/src/components/views/right_panel/VerificationPanel.tsx
+++ b/src/components/views/right_panel/VerificationPanel.tsx
@@ -22,6 +22,7 @@ import {verificationMethods} from 'matrix-js-sdk/src/crypto';
 import {SCAN_QR_CODE_METHOD} from "matrix-js-sdk/src/crypto/verification/QRCode";
 import {VerificationRequest} from "matrix-js-sdk/src/crypto/verification/request/VerificationRequest";
 import {RoomMember} from "matrix-js-sdk/src/models/room-member";
+import { User } from "matrix-js-sdk/src/models/user";
 import {ReciprocateQRCode} from "matrix-js-sdk/src/crypto/verification/QRCode";
 import {SAS} from "matrix-js-sdk/src/crypto/verification/SAS";
 
@@ -51,7 +52,7 @@ enum VerificationPhase {
 interface IProps {
     layout: string;
     request: VerificationRequest;
-    member: RoomMember;
+    member: RoomMember | User;
     phase: VerificationPhase;
     onClose: () => void;
     isRoomEncrypted: boolean;
@@ -134,7 +135,7 @@ export default class VerificationPanel extends React.PureComponent<IProps, IStat
             qrBlock = <div className="mx_UserInfo_container">
                 <h3>{_t("Verify by scanning")}</h3>
                 <p>{_t("Ask %(displayName)s to scan your code:", {
-                    displayName: member.displayName || member.name || member.userId,
+                    displayName: (member as User).displayName || (member as RoomMember).name || member.userId,
                 })}</p>
 
                 <div className="mx_VerificationPanel_qrCode">
@@ -205,7 +206,7 @@ export default class VerificationPanel extends React.PureComponent<IProps, IStat
         const description = request.isSelfVerification ?
             _t("Almost there! Is your other session showing the same shield?") :
             _t("Almost there! Is %(displayName)s showing the same shield?", {
-                displayName: member.displayName || member.name || member.userId,
+                displayName: (member as User).displayName || (member as RoomMember).name || member.userId,
             });
         let body: JSX.Element;
         if (this.state.reciprocateQREvent) {
@@ -264,7 +265,7 @@ export default class VerificationPanel extends React.PureComponent<IProps, IStat
             }
         } else {
             description = _t("You've successfully verified %(displayName)s!", {
-                displayName: member.displayName || member.name || member.userId,
+                displayName: (member as User).displayName || (member as RoomMember).name || member.userId,
             });
         }
 
@@ -302,7 +303,7 @@ export default class VerificationPanel extends React.PureComponent<IProps, IStat
                 text = _t("You cancelled verification on your other session.");
             } else {
                 text = _t("%(displayName)s cancelled verification.", {
-                    displayName: member.displayName || member.name || member.userId,
+                    displayName: (member as User).displayName || (member as RoomMember).name || member.userId,
                 });
             }
             text = `${text} ${startAgainInstruction}`;
@@ -325,7 +326,7 @@ export default class VerificationPanel extends React.PureComponent<IProps, IStat
     public render() {
         const {member, phase, request} = this.props;
 
-        const displayName = member.displayName || member.name || member.userId;
+        const displayName = (member as User).displayName || (member as RoomMember).name || member.userId;
 
         switch (phase) {
             case PHASE_READY:
diff --git a/src/components/views/rooms/EventTile.tsx b/src/components/views/rooms/EventTile.tsx
index f500a50577..0099bf73fb 100644
--- a/src/components/views/rooms/EventTile.tsx
+++ b/src/components/views/rooms/EventTile.tsx
@@ -378,7 +378,7 @@ export default class EventTile extends React.Component<IProps, IState> {
             EventType.RoomMessage,
             EventType.RoomMessageEncrypted,
         ];
-        if (!simpleSendableEvents.includes(this.props.mxEvent.getType())) return false;
+        if (!simpleSendableEvents.includes(this.props.mxEvent.getType() as EventType)) return false;
 
         // Default case
         return true;
diff --git a/src/components/views/settings/tabs/room/BridgeSettingsTab.tsx b/src/components/views/settings/tabs/room/BridgeSettingsTab.tsx
index 8d886a191e..25dfe2f151 100644
--- a/src/components/views/settings/tabs/room/BridgeSettingsTab.tsx
+++ b/src/components/views/settings/tabs/room/BridgeSettingsTab.tsx
@@ -44,14 +44,11 @@ export default class BridgeSettingsTab extends React.Component<IProps> {
         return <BridgeTile key={event.getId()} room={room} ev={event} />;
     }
 
-    static getBridgeStateEvents(roomId: string) {
+    static getBridgeStateEvents(roomId: string): MatrixEvent[] {
         const client = MatrixClientPeg.get();
         const roomState = client.getRoom(roomId).currentState;
 
-        return BRIDGE_EVENT_TYPES.map(typeName => {
-            const events = roomState.events.get(typeName);
-            return events ? Array.from(events.values()) : [];
-        }).flat(1);
+        return BRIDGE_EVENT_TYPES.map(typeName => roomState.getStateEvents(typeName)).flat(1);
     }
 
     render() {
diff --git a/src/dispatcher/payloads/SetRightPanelPhasePayload.ts b/src/dispatcher/payloads/SetRightPanelPhasePayload.ts
index 430fad6145..a4dcb8cfe1 100644
--- a/src/dispatcher/payloads/SetRightPanelPhasePayload.ts
+++ b/src/dispatcher/payloads/SetRightPanelPhasePayload.ts
@@ -17,6 +17,7 @@ limitations under the License.
 import { VerificationRequest } from "matrix-js-sdk/src/crypto/verification/request/VerificationRequest";
 import { Room } from "matrix-js-sdk/src/models/room";
 import { RoomMember } from "matrix-js-sdk/src/models/room-member";
+import { User } from "matrix-js-sdk/src/models/user";
 import { RightPanelPhases } from "../../stores/RightPanelStorePhases";
 import { ActionPayload } from "../payloads";
 import { Action } from "../actions";
@@ -29,7 +30,7 @@ export interface SetRightPanelPhasePayload extends ActionPayload {
 }
 
 export interface SetRightPanelPhaseRefireParams {
-    member?: RoomMember;
+    member?: RoomMember | User;
     verificationRequest?: VerificationRequest;
     groupId?: string;
     groupRoomId?: string;
diff --git a/src/hooks/useAccountData.ts b/src/hooks/useAccountData.ts
index fe71ed9ecd..0384b3bf77 100644
--- a/src/hooks/useAccountData.ts
+++ b/src/hooks/useAccountData.ts
@@ -21,11 +21,11 @@ import {Room} from "matrix-js-sdk/src/models/room";
 
 import {useEventEmitter} from "./useEventEmitter";
 
-const tryGetContent = (ev?: MatrixEvent) => ev ? ev.getContent() : undefined;
+const tryGetContent = <T extends {}>(ev?: MatrixEvent) => ev ? ev.getContent<T>() : undefined;
 
 // Hook to simplify listening to Matrix account data
 export const useAccountData = <T extends {}>(cli: MatrixClient, eventType: string) => {
-    const [value, setValue] = useState<T>(() => tryGetContent(cli.getAccountData(eventType)));
+    const [value, setValue] = useState<T>(() => tryGetContent<T>(cli.getAccountData(eventType)));
 
     const handler = useCallback((event) => {
         if (event.getType() !== eventType) return;
@@ -38,7 +38,7 @@ export const useAccountData = <T extends {}>(cli: MatrixClient, eventType: strin
 
 // Hook to simplify listening to Matrix room account data
 export const useRoomAccountData = <T extends {}>(room: Room, eventType: string) => {
-    const [value, setValue] = useState<T>(() => tryGetContent(room.getAccountData(eventType)));
+    const [value, setValue] = useState<T>(() => tryGetContent<T>(room.getAccountData(eventType)));
 
     const handler = useCallback((event) => {
         if (event.getType() !== eventType) return;
diff --git a/src/indexing/EventIndex.ts b/src/indexing/EventIndex.ts
index b6289969bd..c36f96f368 100644
--- a/src/indexing/EventIndex.ts
+++ b/src/indexing/EventIndex.ts
@@ -300,7 +300,7 @@ export default class EventIndex extends EventEmitter {
     }
 
     private eventToJson(ev: MatrixEvent) {
-        const jsonEvent = ev.toJSON();
+        const jsonEvent: any = ev.toJSON();
         const e = ev.isEncrypted() ? jsonEvent.decrypted : jsonEvent;
 
         if (ev.isEncrypted()) {
diff --git a/src/stores/WidgetEchoStore.ts b/src/stores/WidgetEchoStore.ts
index 09120d6108..0b0be50541 100644
--- a/src/stores/WidgetEchoStore.ts
+++ b/src/stores/WidgetEchoStore.ts
@@ -16,8 +16,8 @@ limitations under the License.
 
 import EventEmitter from 'events';
 import { IWidget } from 'matrix-widget-api';
-import MatrixEvent from "matrix-js-sdk/src/models/event";
-import {WidgetType} from "../widgets/WidgetType";
+import { MatrixEvent } from "matrix-js-sdk/src/models/event";
+import { WidgetType } from "../widgets/WidgetType";
 
 /**
  * Acts as a place to get & set widget state, storing local echo state and
diff --git a/src/stores/widgets/StopGapWidget.ts b/src/stores/widgets/StopGapWidget.ts
index 397d637125..6dcaf7abd7 100644
--- a/src/stores/widgets/StopGapWidget.ts
+++ b/src/stores/widgets/StopGapWidget.ts
@@ -51,7 +51,7 @@ import ThemeWatcher from "../../settings/watchers/ThemeWatcher";
 import {getCustomTheme} from "../../theme";
 import CountlyAnalytics from "../../CountlyAnalytics";
 import { ElementWidgetCapabilities } from "./ElementWidgetCapabilities";
-import { MatrixEvent } from "matrix-js-sdk/src/models/event";
+import { MatrixEvent, IEvent } from "matrix-js-sdk/src/models/event";
 import { ELEMENT_CLIENT_ID } from "../../identifiers";
 import { getUserLanguage } from "../../languageHandler";
 
@@ -415,7 +415,7 @@ export class StopGapWidget extends EventEmitter {
     private feedEvent(ev: MatrixEvent) {
         if (!this.messaging) return;
 
-        const raw = ev.event;
+        const raw = ev.event as IEvent;
         this.messaging.feedEvent(raw).catch(e => {
             console.error("Error sending event to widget: ", e);
         });
diff --git a/src/stores/widgets/StopGapWidgetDriver.ts b/src/stores/widgets/StopGapWidgetDriver.ts
index 25e81c47a2..5218e4a0bc 100644
--- a/src/stores/widgets/StopGapWidgetDriver.ts
+++ b/src/stores/widgets/StopGapWidgetDriver.ts
@@ -145,7 +145,7 @@ export class StopGapWidgetDriver extends WidgetDriver {
         return {roomId, eventId: r.event_id};
     }
 
-    public async readRoomEvents(eventType: string, msgtype: string | undefined, limit: number): Promise<MatrixEvent[]> {
+    public async readRoomEvents(eventType: string, msgtype: string | undefined, limit: number): Promise<object[]> {
         limit = limit > 0 ? Math.min(limit, 25) : 25; // arbitrary choice
 
         const client = MatrixClientPeg.get();
@@ -167,9 +167,7 @@ export class StopGapWidgetDriver extends WidgetDriver {
         return results.map(e => e.event);
     }
 
-    public async readStateEvents(
-        eventType: string, stateKey: string | undefined, limit: number,
-    ): Promise<MatrixEvent[]> {
+    public async readStateEvents(eventType: string, stateKey: string | undefined, limit: number): Promise<object[]> {
         limit = limit > 0 ? Math.min(limit, 100) : 100; // arbitrary choice
 
         const client = MatrixClientPeg.get();
@@ -178,7 +176,7 @@ export class StopGapWidgetDriver extends WidgetDriver {
         if (!client || !roomId || !room) throw new Error("Not in a room or not attached to a client");
 
         const results: MatrixEvent[] = [];
-        const state = room.currentState.events.get(eventType);
+        const state: Map<string, MatrixEvent> = room.currentState.events.get(eventType);
         if (state) {
             if (stateKey === "" || !!stateKey) {
                 const forKey = state.get(stateKey);
diff --git a/src/utils/DMRoomMap.ts b/src/utils/DMRoomMap.ts
index b166674043..3e554f145d 100644
--- a/src/utils/DMRoomMap.ts
+++ b/src/utils/DMRoomMap.ts
@@ -14,11 +14,11 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import {MatrixClientPeg} from '../MatrixClientPeg';
-import {uniq} from "lodash";
-import {Room} from "matrix-js-sdk/src/models/room";
-import {Event} from "matrix-js-sdk/src/models/event";
-import {MatrixClient} from "matrix-js-sdk/src/client";
+import { uniq } from "lodash";
+import { Room } from "matrix-js-sdk/src/models/room";
+import { MatrixClient } from "matrix-js-sdk/src/client";
+
+import { MatrixClientPeg } from '../MatrixClientPeg';
 
 /**
  * Class that takes a Matrix Client and flips the m.direct map
@@ -30,15 +30,13 @@ import {MatrixClient} from "matrix-js-sdk/src/client";
 export default class DMRoomMap {
     private static sharedInstance: DMRoomMap;
 
-    private matrixClient: MatrixClient;
     // TODO: convert these to maps
     private roomToUser: {[key: string]: string} = null;
     private userToRooms: {[key: string]: string[]} = null;
     private hasSentOutPatchDirectAccountDataPatch: boolean;
-    private mDirectEvent: Event;
+    private mDirectEvent: object;
 
-    constructor(matrixClient) {
-        this.matrixClient = matrixClient;
+    constructor(private readonly matrixClient: MatrixClient) {
         // see onAccountData
         this.hasSentOutPatchDirectAccountDataPatch = false;
 
diff --git a/src/utils/WidgetUtils.ts b/src/utils/WidgetUtils.ts
index c67f3bad13..7ff0529363 100644
--- a/src/utils/WidgetUtils.ts
+++ b/src/utils/WidgetUtils.ts
@@ -392,7 +392,7 @@ export default class WidgetUtils {
         }
         const widgets = client.getAccountData('m.widgets');
         if (!widgets) return;
-        const userWidgets: IWidgetEvent[] = widgets.getContent() || {};
+        const userWidgets: Record<string, IWidgetEvent> = widgets.getContent() || {};
         Object.entries(userWidgets).forEach(([key, widget]) => {
             if (widget.content && widget.content.type === "m.integration_manager") {
                 delete userWidgets[key];
diff --git a/test/DecryptionFailureTracker-test.js b/test/DecryptionFailureTracker-test.js
index 7a6a42ef55..bc751ba44e 100644
--- a/test/DecryptionFailureTracker-test.js
+++ b/test/DecryptionFailureTracker-test.js
@@ -30,9 +30,7 @@ function createFailedDecryptionEvent() {
     const event = new MatrixEvent({
         event_id: "event-id-" + Math.random().toString(16).slice(2),
     });
-    event._setClearData(
-        event._badEncryptedMessage(":("),
-    );
+    event.setClearData(event.badEncryptedMessage(":("));
     return event;
 }
 
@@ -67,7 +65,7 @@ describe('DecryptionFailureTracker', function() {
         tracker.eventDecrypted(decryptedEvent, err);
 
         // Indicate successful decryption: clear data can be anything where the msgtype is not m.bad.encrypted
-        decryptedEvent._setClearData({});
+        decryptedEvent.setClearData({});
         tracker.eventDecrypted(decryptedEvent, null);
 
         // Pretend "now" is Infinity